xref: /openbmc/linux/net/nfc/nci/hci.c (revision 4f6cce39)
1 /*
2  *  The NFC Controller Interface is the communication protocol between an
3  *  NFC Controller (NFCC) and a Device Host (DH).
4  *  This is the HCI over NCI implementation, as specified in the 10.2
5  *  section of the NCI 1.1 specification.
6  *
7  *  Copyright (C) 2014  STMicroelectronics SAS. All rights reserved.
8  *
9  *  This program is free software; you can redistribute it and/or modify
10  *  it under the terms of the GNU General Public License version 2
11  *  as published by the Free Software Foundation
12  *
13  *  This program is distributed in the hope that it will be useful,
14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  *  GNU General Public License for more details.
17  *
18  *  You should have received a copy of the GNU General Public License
19  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
20  *
21  */
22 
23 #include <linux/skbuff.h>
24 
25 #include "../nfc.h"
26 #include <net/nfc/nci.h>
27 #include <net/nfc/nci_core.h>
28 #include <linux/nfc.h>
29 
30 struct nci_data {
31 	u8              conn_id;
32 	u8              pipe;
33 	u8              cmd;
34 	const u8        *data;
35 	u32             data_len;
36 } __packed;
37 
38 struct nci_hci_create_pipe_params {
39 	u8 src_gate;
40 	u8 dest_host;
41 	u8 dest_gate;
42 } __packed;
43 
44 struct nci_hci_create_pipe_resp {
45 	u8 src_host;
46 	u8 src_gate;
47 	u8 dest_host;
48 	u8 dest_gate;
49 	u8 pipe;
50 } __packed;
51 
52 struct nci_hci_delete_pipe_noti {
53 	u8 pipe;
54 } __packed;
55 
56 struct nci_hci_all_pipe_cleared_noti {
57 	u8 host;
58 } __packed;
59 
60 struct nci_hcp_message {
61 	u8 header;      /* type -cmd,evt,rsp- + instruction */
62 	u8 data[];
63 } __packed;
64 
65 struct nci_hcp_packet {
66 	u8 header;      /* cbit+pipe */
67 	struct nci_hcp_message message;
68 } __packed;
69 
70 #define NCI_HCI_ANY_SET_PARAMETER  0x01
71 #define NCI_HCI_ANY_GET_PARAMETER  0x02
72 #define NCI_HCI_ANY_CLOSE_PIPE     0x04
73 #define NCI_HCI_ADM_CLEAR_ALL_PIPE 0x14
74 
75 #define NCI_HFP_NO_CHAINING        0x80
76 
77 #define NCI_NFCEE_ID_HCI                0x80
78 
79 #define NCI_EVT_HOT_PLUG           0x03
80 
81 #define NCI_HCI_ADMIN_PARAM_SESSION_IDENTITY       0x01
82 #define NCI_HCI_ADM_CREATE_PIPE			0x10
83 #define NCI_HCI_ADM_DELETE_PIPE			0x11
84 
85 /* HCP headers */
86 #define NCI_HCI_HCP_PACKET_HEADER_LEN      1
87 #define NCI_HCI_HCP_MESSAGE_HEADER_LEN     1
88 #define NCI_HCI_HCP_HEADER_LEN             2
89 
90 /* HCP types */
91 #define NCI_HCI_HCP_COMMAND        0x00
92 #define NCI_HCI_HCP_EVENT          0x01
93 #define NCI_HCI_HCP_RESPONSE       0x02
94 
95 #define NCI_HCI_ADM_NOTIFY_PIPE_CREATED     0x12
96 #define NCI_HCI_ADM_NOTIFY_PIPE_DELETED     0x13
97 #define NCI_HCI_ADM_NOTIFY_ALL_PIPE_CLEARED 0x15
98 
99 #define NCI_HCI_FRAGMENT           0x7f
100 #define NCI_HCP_HEADER(type, instr) ((((type) & 0x03) << 6) |\
101 				      ((instr) & 0x3f))
102 
103 #define NCI_HCP_MSG_GET_TYPE(header) ((header & 0xc0) >> 6)
104 #define NCI_HCP_MSG_GET_CMD(header)  (header & 0x3f)
105 #define NCI_HCP_MSG_GET_PIPE(header) (header & 0x7f)
106 
107 static int nci_hci_result_to_errno(u8 result)
108 {
109 	switch (result) {
110 	case NCI_HCI_ANY_OK:
111 		return 0;
112 	case NCI_HCI_ANY_E_REG_PAR_UNKNOWN:
113 		return -EOPNOTSUPP;
114 	case NCI_HCI_ANY_E_TIMEOUT:
115 		return -ETIME;
116 	default:
117 		return -1;
118 	}
119 }
120 
121 /* HCI core */
122 static void nci_hci_reset_pipes(struct nci_hci_dev *hdev)
123 {
124 	int i;
125 
126 	for (i = 0; i < NCI_HCI_MAX_PIPES; i++) {
127 		hdev->pipes[i].gate = NCI_HCI_INVALID_GATE;
128 		hdev->pipes[i].host = NCI_HCI_INVALID_HOST;
129 	}
130 	memset(hdev->gate2pipe, NCI_HCI_INVALID_PIPE, sizeof(hdev->gate2pipe));
131 }
132 
133 static void nci_hci_reset_pipes_per_host(struct nci_dev *ndev, u8 host)
134 {
135 	int i;
136 
137 	for (i = 0; i < NCI_HCI_MAX_PIPES; i++) {
138 		if (ndev->hci_dev->pipes[i].host == host) {
139 			ndev->hci_dev->pipes[i].gate = NCI_HCI_INVALID_GATE;
140 			ndev->hci_dev->pipes[i].host = NCI_HCI_INVALID_HOST;
141 		}
142 	}
143 }
144 
145 /* Fragment HCI data over NCI packet.
146  * NFC Forum NCI 10.2.2 Data Exchange:
147  * The payload of the Data Packets sent on the Logical Connection SHALL be
148  * valid HCP packets, as defined within [ETSI_102622]. Each Data Packet SHALL
149  * contain a single HCP packet. NCI Segmentation and Reassembly SHALL NOT be
150  * applied to Data Messages in either direction. The HCI fragmentation mechanism
151  * is used if required.
152  */
153 static int nci_hci_send_data(struct nci_dev *ndev, u8 pipe,
154 			     const u8 data_type, const u8 *data,
155 			     size_t data_len)
156 {
157 	struct nci_conn_info    *conn_info;
158 	struct sk_buff *skb;
159 	int len, i, r;
160 	u8 cb = pipe;
161 
162 	conn_info = ndev->hci_dev->conn_info;
163 	if (!conn_info)
164 		return -EPROTO;
165 
166 	i = 0;
167 	skb = nci_skb_alloc(ndev, conn_info->max_pkt_payload_len +
168 			    NCI_DATA_HDR_SIZE, GFP_KERNEL);
169 	if (!skb)
170 		return -ENOMEM;
171 
172 	skb_reserve(skb, NCI_DATA_HDR_SIZE + 2);
173 	*skb_push(skb, 1) = data_type;
174 
175 	do {
176 		len = conn_info->max_pkt_payload_len;
177 
178 		/* If last packet add NCI_HFP_NO_CHAINING */
179 		if (i + conn_info->max_pkt_payload_len -
180 		    (skb->len + 1) >= data_len) {
181 			cb |= NCI_HFP_NO_CHAINING;
182 			len = data_len - i;
183 		} else {
184 			len = conn_info->max_pkt_payload_len - skb->len - 1;
185 		}
186 
187 		*skb_push(skb, 1) = cb;
188 
189 		if (len > 0)
190 			memcpy(skb_put(skb, len), data + i, len);
191 
192 		r = nci_send_data(ndev, conn_info->conn_id, skb);
193 		if (r < 0)
194 			return r;
195 
196 		i += len;
197 
198 		if (i < data_len) {
199 			skb = nci_skb_alloc(ndev,
200 					    conn_info->max_pkt_payload_len +
201 					    NCI_DATA_HDR_SIZE, GFP_KERNEL);
202 			if (!skb)
203 				return -ENOMEM;
204 
205 			skb_reserve(skb, NCI_DATA_HDR_SIZE + 1);
206 		}
207 	} while (i < data_len);
208 
209 	return i;
210 }
211 
212 static void nci_hci_send_data_req(struct nci_dev *ndev, unsigned long opt)
213 {
214 	struct nci_data *data = (struct nci_data *)opt;
215 
216 	nci_hci_send_data(ndev, data->pipe, data->cmd,
217 			  data->data, data->data_len);
218 }
219 
220 int nci_hci_send_event(struct nci_dev *ndev, u8 gate, u8 event,
221 		       const u8 *param, size_t param_len)
222 {
223 	u8 pipe = ndev->hci_dev->gate2pipe[gate];
224 
225 	if (pipe == NCI_HCI_INVALID_PIPE)
226 		return -EADDRNOTAVAIL;
227 
228 	return nci_hci_send_data(ndev, pipe,
229 			NCI_HCP_HEADER(NCI_HCI_HCP_EVENT, event),
230 			param, param_len);
231 }
232 EXPORT_SYMBOL(nci_hci_send_event);
233 
234 int nci_hci_send_cmd(struct nci_dev *ndev, u8 gate, u8 cmd,
235 		     const u8 *param, size_t param_len,
236 		     struct sk_buff **skb)
237 {
238 	struct nci_hcp_message *message;
239 	struct nci_conn_info   *conn_info;
240 	struct nci_data data;
241 	int r;
242 	u8 pipe = ndev->hci_dev->gate2pipe[gate];
243 
244 	if (pipe == NCI_HCI_INVALID_PIPE)
245 		return -EADDRNOTAVAIL;
246 
247 	conn_info = ndev->hci_dev->conn_info;
248 	if (!conn_info)
249 		return -EPROTO;
250 
251 	data.conn_id = conn_info->conn_id;
252 	data.pipe = pipe;
253 	data.cmd = NCI_HCP_HEADER(NCI_HCI_HCP_COMMAND, cmd);
254 	data.data = param;
255 	data.data_len = param_len;
256 
257 	r = nci_request(ndev, nci_hci_send_data_req, (unsigned long)&data,
258 			msecs_to_jiffies(NCI_DATA_TIMEOUT));
259 	if (r == NCI_STATUS_OK) {
260 		message = (struct nci_hcp_message *)conn_info->rx_skb->data;
261 		r = nci_hci_result_to_errno(
262 			NCI_HCP_MSG_GET_CMD(message->header));
263 		skb_pull(conn_info->rx_skb, NCI_HCI_HCP_MESSAGE_HEADER_LEN);
264 
265 		if (!r && skb)
266 			*skb = conn_info->rx_skb;
267 	}
268 
269 	return r;
270 }
271 EXPORT_SYMBOL(nci_hci_send_cmd);
272 
273 int nci_hci_clear_all_pipes(struct nci_dev *ndev)
274 {
275 	int r;
276 
277 	r = nci_hci_send_cmd(ndev, NCI_HCI_ADMIN_GATE,
278 			     NCI_HCI_ADM_CLEAR_ALL_PIPE, NULL, 0, NULL);
279 	if (r < 0)
280 		return r;
281 
282 	nci_hci_reset_pipes(ndev->hci_dev);
283 	return r;
284 }
285 EXPORT_SYMBOL(nci_hci_clear_all_pipes);
286 
287 static void nci_hci_event_received(struct nci_dev *ndev, u8 pipe,
288 				   u8 event, struct sk_buff *skb)
289 {
290 	if (ndev->ops->hci_event_received)
291 		ndev->ops->hci_event_received(ndev, pipe, event, skb);
292 }
293 
294 static void nci_hci_cmd_received(struct nci_dev *ndev, u8 pipe,
295 				 u8 cmd, struct sk_buff *skb)
296 {
297 	u8 gate = ndev->hci_dev->pipes[pipe].gate;
298 	u8 status = NCI_HCI_ANY_OK | ~NCI_HCI_FRAGMENT;
299 	u8 dest_gate, new_pipe;
300 	struct nci_hci_create_pipe_resp *create_info;
301 	struct nci_hci_delete_pipe_noti *delete_info;
302 	struct nci_hci_all_pipe_cleared_noti *cleared_info;
303 
304 	pr_debug("from gate %x pipe %x cmd %x\n", gate, pipe, cmd);
305 
306 	switch (cmd) {
307 	case NCI_HCI_ADM_NOTIFY_PIPE_CREATED:
308 		if (skb->len != 5) {
309 			status = NCI_HCI_ANY_E_NOK;
310 			goto exit;
311 		}
312 		create_info = (struct nci_hci_create_pipe_resp *)skb->data;
313 		dest_gate = create_info->dest_gate;
314 		new_pipe = create_info->pipe;
315 
316 		/* Save the new created pipe and bind with local gate,
317 		 * the description for skb->data[3] is destination gate id
318 		 * but since we received this cmd from host controller, we
319 		 * are the destination and it is our local gate
320 		 */
321 		ndev->hci_dev->gate2pipe[dest_gate] = new_pipe;
322 		ndev->hci_dev->pipes[new_pipe].gate = dest_gate;
323 		ndev->hci_dev->pipes[new_pipe].host =
324 						create_info->src_host;
325 		break;
326 	case NCI_HCI_ANY_OPEN_PIPE:
327 		/* If the pipe is not created report an error */
328 		if (gate == NCI_HCI_INVALID_GATE) {
329 			status = NCI_HCI_ANY_E_NOK;
330 			goto exit;
331 		}
332 		break;
333 	case NCI_HCI_ADM_NOTIFY_PIPE_DELETED:
334 		if (skb->len != 1) {
335 			status = NCI_HCI_ANY_E_NOK;
336 			goto exit;
337 		}
338 		delete_info = (struct nci_hci_delete_pipe_noti *)skb->data;
339 
340 		ndev->hci_dev->pipes[delete_info->pipe].gate =
341 						NCI_HCI_INVALID_GATE;
342 		ndev->hci_dev->pipes[delete_info->pipe].host =
343 						NCI_HCI_INVALID_HOST;
344 		break;
345 	case NCI_HCI_ADM_NOTIFY_ALL_PIPE_CLEARED:
346 		if (skb->len != 1) {
347 			status = NCI_HCI_ANY_E_NOK;
348 			goto exit;
349 		}
350 
351 		cleared_info =
352 			(struct nci_hci_all_pipe_cleared_noti *)skb->data;
353 		nci_hci_reset_pipes_per_host(ndev, cleared_info->host);
354 		break;
355 	default:
356 		pr_debug("Discarded unknown cmd %x to gate %x\n", cmd, gate);
357 		break;
358 	}
359 
360 	if (ndev->ops->hci_cmd_received)
361 		ndev->ops->hci_cmd_received(ndev, pipe, cmd, skb);
362 
363 exit:
364 	nci_hci_send_data(ndev, pipe, status, NULL, 0);
365 
366 	kfree_skb(skb);
367 }
368 
369 static void nci_hci_resp_received(struct nci_dev *ndev, u8 pipe,
370 				  u8 result, struct sk_buff *skb)
371 {
372 	struct nci_conn_info    *conn_info;
373 	u8 status = result;
374 
375 	conn_info = ndev->hci_dev->conn_info;
376 	if (!conn_info) {
377 		status = NCI_STATUS_REJECTED;
378 		goto exit;
379 	}
380 
381 	conn_info->rx_skb = skb;
382 
383 exit:
384 	nci_req_complete(ndev, NCI_STATUS_OK);
385 }
386 
387 /* Receive hcp message for pipe, with type and cmd.
388  * skb contains optional message data only.
389  */
390 static void nci_hci_hcp_message_rx(struct nci_dev *ndev, u8 pipe,
391 				   u8 type, u8 instruction, struct sk_buff *skb)
392 {
393 	switch (type) {
394 	case NCI_HCI_HCP_RESPONSE:
395 		nci_hci_resp_received(ndev, pipe, instruction, skb);
396 		break;
397 	case NCI_HCI_HCP_COMMAND:
398 		nci_hci_cmd_received(ndev, pipe, instruction, skb);
399 		break;
400 	case NCI_HCI_HCP_EVENT:
401 		nci_hci_event_received(ndev, pipe, instruction, skb);
402 		break;
403 	default:
404 		pr_err("UNKNOWN MSG Type %d, instruction=%d\n",
405 		       type, instruction);
406 		kfree_skb(skb);
407 		break;
408 	}
409 
410 	nci_req_complete(ndev, NCI_STATUS_OK);
411 }
412 
413 static void nci_hci_msg_rx_work(struct work_struct *work)
414 {
415 	struct nci_hci_dev *hdev =
416 		container_of(work, struct nci_hci_dev, msg_rx_work);
417 	struct sk_buff *skb;
418 	struct nci_hcp_message *message;
419 	u8 pipe, type, instruction;
420 
421 	while ((skb = skb_dequeue(&hdev->msg_rx_queue)) != NULL) {
422 		pipe = NCI_HCP_MSG_GET_PIPE(skb->data[0]);
423 		skb_pull(skb, NCI_HCI_HCP_PACKET_HEADER_LEN);
424 		message = (struct nci_hcp_message *)skb->data;
425 		type = NCI_HCP_MSG_GET_TYPE(message->header);
426 		instruction = NCI_HCP_MSG_GET_CMD(message->header);
427 		skb_pull(skb, NCI_HCI_HCP_MESSAGE_HEADER_LEN);
428 
429 		nci_hci_hcp_message_rx(hdev->ndev, pipe,
430 				       type, instruction, skb);
431 	}
432 }
433 
434 void nci_hci_data_received_cb(void *context,
435 			      struct sk_buff *skb, int err)
436 {
437 	struct nci_dev *ndev = (struct nci_dev *)context;
438 	struct nci_hcp_packet *packet;
439 	u8 pipe, type;
440 	struct sk_buff *hcp_skb;
441 	struct sk_buff *frag_skb;
442 	int msg_len;
443 
444 	pr_debug("\n");
445 
446 	if (err) {
447 		nci_req_complete(ndev, err);
448 		return;
449 	}
450 
451 	packet = (struct nci_hcp_packet *)skb->data;
452 	if ((packet->header & ~NCI_HCI_FRAGMENT) == 0) {
453 		skb_queue_tail(&ndev->hci_dev->rx_hcp_frags, skb);
454 		return;
455 	}
456 
457 	/* it's the last fragment. Does it need re-aggregation? */
458 	if (skb_queue_len(&ndev->hci_dev->rx_hcp_frags)) {
459 		pipe = NCI_HCP_MSG_GET_PIPE(packet->header);
460 		skb_queue_tail(&ndev->hci_dev->rx_hcp_frags, skb);
461 
462 		msg_len = 0;
463 		skb_queue_walk(&ndev->hci_dev->rx_hcp_frags, frag_skb) {
464 			msg_len += (frag_skb->len -
465 				    NCI_HCI_HCP_PACKET_HEADER_LEN);
466 		}
467 
468 		hcp_skb = nfc_alloc_recv_skb(NCI_HCI_HCP_PACKET_HEADER_LEN +
469 					     msg_len, GFP_KERNEL);
470 		if (!hcp_skb) {
471 			nci_req_complete(ndev, -ENOMEM);
472 			return;
473 		}
474 
475 		*skb_put(hcp_skb, NCI_HCI_HCP_PACKET_HEADER_LEN) = pipe;
476 
477 		skb_queue_walk(&ndev->hci_dev->rx_hcp_frags, frag_skb) {
478 			msg_len = frag_skb->len - NCI_HCI_HCP_PACKET_HEADER_LEN;
479 			memcpy(skb_put(hcp_skb, msg_len), frag_skb->data +
480 			       NCI_HCI_HCP_PACKET_HEADER_LEN, msg_len);
481 		}
482 
483 		skb_queue_purge(&ndev->hci_dev->rx_hcp_frags);
484 	} else {
485 		packet->header &= NCI_HCI_FRAGMENT;
486 		hcp_skb = skb;
487 	}
488 
489 	/* if this is a response, dispatch immediately to
490 	 * unblock waiting cmd context. Otherwise, enqueue to dispatch
491 	 * in separate context where handler can also execute command.
492 	 */
493 	packet = (struct nci_hcp_packet *)hcp_skb->data;
494 	type = NCI_HCP_MSG_GET_TYPE(packet->message.header);
495 	if (type == NCI_HCI_HCP_RESPONSE) {
496 		pipe = NCI_HCP_MSG_GET_PIPE(packet->header);
497 		skb_pull(hcp_skb, NCI_HCI_HCP_PACKET_HEADER_LEN);
498 		nci_hci_hcp_message_rx(ndev, pipe, type,
499 				       NCI_STATUS_OK, hcp_skb);
500 	} else {
501 		skb_queue_tail(&ndev->hci_dev->msg_rx_queue, hcp_skb);
502 		schedule_work(&ndev->hci_dev->msg_rx_work);
503 	}
504 }
505 
506 int nci_hci_open_pipe(struct nci_dev *ndev, u8 pipe)
507 {
508 	struct nci_data data;
509 	struct nci_conn_info    *conn_info;
510 
511 	conn_info = ndev->hci_dev->conn_info;
512 	if (!conn_info)
513 		return -EPROTO;
514 
515 	data.conn_id = conn_info->conn_id;
516 	data.pipe = pipe;
517 	data.cmd = NCI_HCP_HEADER(NCI_HCI_HCP_COMMAND,
518 				       NCI_HCI_ANY_OPEN_PIPE);
519 	data.data = NULL;
520 	data.data_len = 0;
521 
522 	return nci_request(ndev, nci_hci_send_data_req,
523 			(unsigned long)&data,
524 			msecs_to_jiffies(NCI_DATA_TIMEOUT));
525 }
526 EXPORT_SYMBOL(nci_hci_open_pipe);
527 
528 static u8 nci_hci_create_pipe(struct nci_dev *ndev, u8 dest_host,
529 			      u8 dest_gate, int *result)
530 {
531 	u8 pipe;
532 	struct sk_buff *skb;
533 	struct nci_hci_create_pipe_params params;
534 	struct nci_hci_create_pipe_resp *resp;
535 
536 	pr_debug("gate=%d\n", dest_gate);
537 
538 	params.src_gate = NCI_HCI_ADMIN_GATE;
539 	params.dest_host = dest_host;
540 	params.dest_gate = dest_gate;
541 
542 	*result = nci_hci_send_cmd(ndev, NCI_HCI_ADMIN_GATE,
543 				   NCI_HCI_ADM_CREATE_PIPE,
544 				   (u8 *)&params, sizeof(params), &skb);
545 	if (*result < 0)
546 		return NCI_HCI_INVALID_PIPE;
547 
548 	resp = (struct nci_hci_create_pipe_resp *)skb->data;
549 	pipe = resp->pipe;
550 	kfree_skb(skb);
551 
552 	pr_debug("pipe created=%d\n", pipe);
553 
554 	return pipe;
555 }
556 
557 static int nci_hci_delete_pipe(struct nci_dev *ndev, u8 pipe)
558 {
559 	pr_debug("\n");
560 
561 	return nci_hci_send_cmd(ndev, NCI_HCI_ADMIN_GATE,
562 				NCI_HCI_ADM_DELETE_PIPE, &pipe, 1, NULL);
563 }
564 
565 int nci_hci_set_param(struct nci_dev *ndev, u8 gate, u8 idx,
566 		      const u8 *param, size_t param_len)
567 {
568 	struct nci_hcp_message *message;
569 	struct nci_conn_info *conn_info;
570 	struct nci_data data;
571 	int r;
572 	u8 *tmp;
573 	u8 pipe = ndev->hci_dev->gate2pipe[gate];
574 
575 	pr_debug("idx=%d to gate %d\n", idx, gate);
576 
577 	if (pipe == NCI_HCI_INVALID_PIPE)
578 		return -EADDRNOTAVAIL;
579 
580 	conn_info = ndev->hci_dev->conn_info;
581 	if (!conn_info)
582 		return -EPROTO;
583 
584 	tmp = kmalloc(1 + param_len, GFP_KERNEL);
585 	if (!tmp)
586 		return -ENOMEM;
587 
588 	*tmp = idx;
589 	memcpy(tmp + 1, param, param_len);
590 
591 	data.conn_id = conn_info->conn_id;
592 	data.pipe = pipe;
593 	data.cmd = NCI_HCP_HEADER(NCI_HCI_HCP_COMMAND,
594 				       NCI_HCI_ANY_SET_PARAMETER);
595 	data.data = tmp;
596 	data.data_len = param_len + 1;
597 
598 	r = nci_request(ndev, nci_hci_send_data_req,
599 			(unsigned long)&data,
600 			msecs_to_jiffies(NCI_DATA_TIMEOUT));
601 	if (r == NCI_STATUS_OK) {
602 		message = (struct nci_hcp_message *)conn_info->rx_skb->data;
603 		r = nci_hci_result_to_errno(
604 			NCI_HCP_MSG_GET_CMD(message->header));
605 		skb_pull(conn_info->rx_skb, NCI_HCI_HCP_MESSAGE_HEADER_LEN);
606 	}
607 
608 	kfree(tmp);
609 	return r;
610 }
611 EXPORT_SYMBOL(nci_hci_set_param);
612 
613 int nci_hci_get_param(struct nci_dev *ndev, u8 gate, u8 idx,
614 		      struct sk_buff **skb)
615 {
616 	struct nci_hcp_message *message;
617 	struct nci_conn_info    *conn_info;
618 	struct nci_data data;
619 	int r;
620 	u8 pipe = ndev->hci_dev->gate2pipe[gate];
621 
622 	pr_debug("idx=%d to gate %d\n", idx, gate);
623 
624 	if (pipe == NCI_HCI_INVALID_PIPE)
625 		return -EADDRNOTAVAIL;
626 
627 	conn_info = ndev->hci_dev->conn_info;
628 	if (!conn_info)
629 		return -EPROTO;
630 
631 	data.conn_id = conn_info->conn_id;
632 	data.pipe = pipe;
633 	data.cmd = NCI_HCP_HEADER(NCI_HCI_HCP_COMMAND,
634 				  NCI_HCI_ANY_GET_PARAMETER);
635 	data.data = &idx;
636 	data.data_len = 1;
637 
638 	r = nci_request(ndev, nci_hci_send_data_req, (unsigned long)&data,
639 			msecs_to_jiffies(NCI_DATA_TIMEOUT));
640 
641 	if (r == NCI_STATUS_OK) {
642 		message = (struct nci_hcp_message *)conn_info->rx_skb->data;
643 		r = nci_hci_result_to_errno(
644 			NCI_HCP_MSG_GET_CMD(message->header));
645 		skb_pull(conn_info->rx_skb, NCI_HCI_HCP_MESSAGE_HEADER_LEN);
646 
647 		if (!r && skb)
648 			*skb = conn_info->rx_skb;
649 	}
650 
651 	return r;
652 }
653 EXPORT_SYMBOL(nci_hci_get_param);
654 
655 int nci_hci_connect_gate(struct nci_dev *ndev,
656 			 u8 dest_host, u8 dest_gate, u8 pipe)
657 {
658 	bool pipe_created = false;
659 	int r;
660 
661 	if (pipe == NCI_HCI_DO_NOT_OPEN_PIPE)
662 		return 0;
663 
664 	if (ndev->hci_dev->gate2pipe[dest_gate] != NCI_HCI_INVALID_PIPE)
665 		return -EADDRINUSE;
666 
667 	if (pipe != NCI_HCI_INVALID_PIPE)
668 		goto open_pipe;
669 
670 	switch (dest_gate) {
671 	case NCI_HCI_LINK_MGMT_GATE:
672 		pipe = NCI_HCI_LINK_MGMT_PIPE;
673 	break;
674 	case NCI_HCI_ADMIN_GATE:
675 		pipe = NCI_HCI_ADMIN_PIPE;
676 	break;
677 	default:
678 		pipe = nci_hci_create_pipe(ndev, dest_host, dest_gate, &r);
679 		if (pipe == NCI_HCI_INVALID_PIPE)
680 			return r;
681 		pipe_created = true;
682 		break;
683 	}
684 
685 open_pipe:
686 	r = nci_hci_open_pipe(ndev, pipe);
687 	if (r < 0) {
688 		if (pipe_created) {
689 			if (nci_hci_delete_pipe(ndev, pipe) < 0) {
690 				/* TODO: Cannot clean by deleting pipe...
691 				 * -> inconsistent state
692 				 */
693 			}
694 		}
695 		return r;
696 	}
697 
698 	ndev->hci_dev->pipes[pipe].gate = dest_gate;
699 	ndev->hci_dev->pipes[pipe].host = dest_host;
700 	ndev->hci_dev->gate2pipe[dest_gate] = pipe;
701 
702 	return 0;
703 }
704 EXPORT_SYMBOL(nci_hci_connect_gate);
705 
706 static int nci_hci_dev_connect_gates(struct nci_dev *ndev,
707 				     u8 gate_count,
708 				     struct nci_hci_gate *gates)
709 {
710 	int r;
711 
712 	while (gate_count--) {
713 		r = nci_hci_connect_gate(ndev, gates->dest_host,
714 					 gates->gate, gates->pipe);
715 		if (r < 0)
716 			return r;
717 		gates++;
718 	}
719 
720 	return 0;
721 }
722 
723 int nci_hci_dev_session_init(struct nci_dev *ndev)
724 {
725 	struct nci_conn_info    *conn_info;
726 	struct sk_buff *skb;
727 	int r;
728 
729 	ndev->hci_dev->count_pipes = 0;
730 	ndev->hci_dev->expected_pipes = 0;
731 
732 	conn_info = ndev->hci_dev->conn_info;
733 	if (!conn_info)
734 		return -EPROTO;
735 
736 	conn_info->data_exchange_cb = nci_hci_data_received_cb;
737 	conn_info->data_exchange_cb_context = ndev;
738 
739 	nci_hci_reset_pipes(ndev->hci_dev);
740 
741 	if (ndev->hci_dev->init_data.gates[0].gate != NCI_HCI_ADMIN_GATE)
742 		return -EPROTO;
743 
744 	r = nci_hci_connect_gate(ndev,
745 				 ndev->hci_dev->init_data.gates[0].dest_host,
746 				 ndev->hci_dev->init_data.gates[0].gate,
747 				 ndev->hci_dev->init_data.gates[0].pipe);
748 	if (r < 0)
749 		return r;
750 
751 	r = nci_hci_get_param(ndev, NCI_HCI_ADMIN_GATE,
752 			      NCI_HCI_ADMIN_PARAM_SESSION_IDENTITY, &skb);
753 	if (r < 0)
754 		return r;
755 
756 	if (skb->len &&
757 	    skb->len == strlen(ndev->hci_dev->init_data.session_id) &&
758 	    !memcmp(ndev->hci_dev->init_data.session_id, skb->data, skb->len) &&
759 	    ndev->ops->hci_load_session) {
760 		/* Restore gate<->pipe table from some proprietary location. */
761 		r = ndev->ops->hci_load_session(ndev);
762 	} else {
763 		r = nci_hci_clear_all_pipes(ndev);
764 		if (r < 0)
765 			goto exit;
766 
767 		r = nci_hci_dev_connect_gates(ndev,
768 					      ndev->hci_dev->init_data.gate_count,
769 					      ndev->hci_dev->init_data.gates);
770 		if (r < 0)
771 			goto exit;
772 
773 		r = nci_hci_set_param(ndev, NCI_HCI_ADMIN_GATE,
774 				      NCI_HCI_ADMIN_PARAM_SESSION_IDENTITY,
775 				      ndev->hci_dev->init_data.session_id,
776 				      strlen(ndev->hci_dev->init_data.session_id));
777 	}
778 
779 exit:
780 	kfree_skb(skb);
781 
782 	return r;
783 }
784 EXPORT_SYMBOL(nci_hci_dev_session_init);
785 
786 struct nci_hci_dev *nci_hci_allocate(struct nci_dev *ndev)
787 {
788 	struct nci_hci_dev *hdev;
789 
790 	hdev = kzalloc(sizeof(*hdev), GFP_KERNEL);
791 	if (!hdev)
792 		return NULL;
793 
794 	skb_queue_head_init(&hdev->rx_hcp_frags);
795 	INIT_WORK(&hdev->msg_rx_work, nci_hci_msg_rx_work);
796 	skb_queue_head_init(&hdev->msg_rx_queue);
797 	hdev->ndev = ndev;
798 
799 	return hdev;
800 }
801